Thermic siphon and method of making the same



April 14, 1931. 1,800,507

THERMIC SIPHON AND METHOD OF MAKING THE. SAME ca. J. CHRISTENSON F1100 Dec.

Q 0 0 0 0-0 0 3 O O O -0 O O O O O O Q 0 6 Q 0 0 O O 0 0 O 6 O 0 O O O 0 O 0 Q 0 0 GQQOOOOO/ i fi rlam Patented Apr. 14, 1931 UNITED STATES PATENT OFFICE GUST J. CHRISTENSON, OF CHICAGO, ILLINOIS, ASSIGNOR TO LOCOMOTIVE FIBEBOX COMPANY, OI CHICAGO, ILLINOIS, A. CORPORATION OF DELAWARE THERMIC SIIHON AND METHOD OF MAKING THE SAME Application filed December 14, 1929. Serial No. 414,024.

This invention relates to improvements in thermic siphons and method of making the same and it consists of the matters hereinafter described and more particularly pointed out in the appended claims.

The thermic siphon with which my invention is more'particularly concerned is of the kind best shown in the Nicholson Patent No. 1,337,720. Such a siphon is employed in 9 the firebox of locomotive boilers and usually has its inlet neck opening through the throat sheet and its outlet or discharge, opening through the crown sheet. Siphons of this kind, increase the water steaming and ciru culating efliciencies of the boiler and act to keep the high end of the crown sheet flooded, even at water levels below normal.

Due to their construction, such sip'hons are expensive to produce. In the Nicholson pat- R ent, before referred to, the siphon was formed from a single piece of sheet metal first cut to a pattern, and then folded along a predetermined line. Thereafter certain forming o ations were carried out and then the assoil ciated edges of the sheet were welded together. This left a welded seam along one end of the body which extended down through the neck, the neck being transversely stayed for strength to the determent of a free 130 uninterrupted circulation. Such a siphon is diflicult to produce, is expensive not only as to labor cost but also because of the accuracy necwsary to make a perfect one and this, of course, often resulted in scrapping the siphon as im erfect following rigid tests. In atent No.- 1,717,033, of June 11, 1929, granted to Walter H. Hinsch and myself, the siphon body was made of one or more parts and a tube was slit and formed for attachment to the body, the tube providing the inlet neck and a part of the closed bottom of the body, the other part of said closed bottom being formed bv a part of the body itself. Such a structure while reducing the cost of making 46 siphons had certain disadvantages which the present invention overcomes. I

The primary object of the invention is to provide a siphon of this kind which can be more easily made without the requirement of expensive apparatus, which can be produced in a maximum size and with a rapidity which will permit the accumulation of a surplus stock thereof ready for trimming to fit the firebox in which a siphon is to be installed.

Another object of the invention is to provide a siphon of this kind which requires no flanging of the parts thereof with a corresponding reduction in cost of production and this without sacrificing strength or rigidity in the finished siphon.

These objects of the invention as well as others together with the many advantages thereof will more fully appear as I proceed with my specification.

In the drawings Fig. 1 is a View in side elevation of one form of siphon made in accordance with my invention and shown as installed in the firebox of a locomotive boiler.

Fig. 2 is a vertical sectional view through the same on an enlarged scale as taken on the line 2-2 of Fig. 1.

Fig. 3 is a horizontal sectional view :tBhrough the same as taken on the line 3- 3 of Fig. 4 is a fragmentary detail view in side elevation showing a modified form of construction.

Referring now in detail to that embodiment of the invention illustrated in the accompanying drawing and more particularly to Figs. 1, 2 and 3 thereof, I provide a length of seamless steel tubing 1 and form a longitudinal slot 2 in what is thereafter the top side thereof, said slot terminating short of the ends of the tube. This tubing as will later appear, forms not only the bottom of the siphon but also the inlet neck as well as an auxiliary or secondary discharge for the siphon.

I then provide a sheet of metal, preferably boiler plate cut to the desired pattern, and operate upon the same to form the body 3 of the siphon. Such a sheet which is of the greatest depth at its transverse median line and shortest at its ends, is folded over upon its self to provide the side walls 44 and an integral rounded end wall 5, the other end wall 6 being formed by welding the shorter ends of the sheet together as at 7 in Fig. 3.

Thus a fiat tubular body is provided which is open at the top and bottom and closed at both ends, one of which is shorter than the other. The side walls of the body are staybolted together as at 8 and the holes for said bolts may be formed in the sheet while in pattern form by punching or said holes may be formed in the flat tubular body by drillmg.

The flat tubular body thus formed will, of course, have its side walls spaced apart a distance approximating the width of the slot 2 and the open bottom endof said body is inserted into said slot and is'then welded thereto as at 9in Fig. 2. Thus there is formed a siphon'having a body open at its top and closed at its ends and further closed at its bottom by a tube having end parts 10 and 11 respectively extending beyond each end of the body. a a

Such a siphon is then-ready for. installation in the firebox of a locomotive boiler. To install such a siphon a longitudinal slot 12 is formed in the crown sheet 13 of the firebox to receive the open top end of the siphon body and openings 14 and 15 respectively are formed in the front and rear sheets 16 and 17 of the firebox to receive the end extensions 11 and 10 respectively of the tube. The tube is cut to fit the spacing of said front and rear sheets and the top end of the body is trimmed to provide the desired depth of body after which said tube extensions and body are inserted in their respective'openings in the associated firebox sheets and then welded thereto as best shown in Figs. 1 and 2'. Such welding, of course, is done from within the firebox. V

With a siphon embodying my invention installed in a firebox as described, itisap;

parent that the welded seams are so disposed as to be out of that zone afiected'by the mechanical abrasive action of the products'of combustion. Again the tube being a relatively long and seamless one, can fiex to accommodate strains and stresses produced by temperaturechanges. In operation, the'entire surface area of the tube and body being subjected totheintense heat of the products of combustion in the firebox, rapidly transmits heat to the water within said tube and body. Owing to the differences in, thermic heads, the hotter and lighter waterin said tube and body is displaced byv the cooler and heavier water in the front throat of the boiler" and a circulation is established from said throat into the tube. The major portion of this water passes up through the body into the boiler waterspace above the crown sheet and the minor portion of the same passes into the back water leg of the boiler. Such steam bubbles as are evolved on the interior surface of thetube and body are swept clean therefrom to pass into the steamspace of the boiler. I r

In Fig. 4 is illustrated a modified form of the invention'in that instead of the rear extension 10 of the tube being secured in the back sheet of the firebox it is swedged down in diameter and formed on a gentle curve to open through the crown sheet 13 at a point spaced to the rear of the body. This manner of forming the rear end extension of the tube is advantageous in that it provides an extra outlet or discharge through, the crown sheet. and this without the formation of any sharp corners or pockets where sediment can accumulate. Again it eliminates the stopping short of the tube at the rear end of the body which would require the formation of a peculiar end at this point, difiicult to make.

Thus with my invention I am enabled to make a siphon in indeed a practical manner which does not require heavy or expensive machinesin the making thereof, other than those now found in the modern boiler shops. Again I am enabled to produce the siphons fast enough to build up a surplus stock any one of which may be trimmed down to meet the particular installation at hand. This ma.-

' terially reduces lay uptime' for the locomotive in which the siphon is to be installed.

In describing the invention, I have referred in detail to the form and arrangement of the parts thereof, as well as the sequence in steps taken in producing saidparts, it is apparent that the same is to be considered merely as illustrative so that I do not wish to be limited thereto except as may be speciiical ly set forth in the appended claims.

I claim as my invention g f 1. T he method of making thermic siphons which consists in providing a flat hollow siphon body, open topand bottom and closed at its ends, in providing a tube having allongitudinal slot in itstop side adapted to re ceive the open bottom end of the siphon body, inserting said end of the body in said slot and then welding it in place therein, said tube having an extension beyond an end of said slot to form an intake for the finished siphon.

2. The method of making thermic siphons which consists in providing a flat hollowsiphon body open at its top and bottom and closed at its ends, i n-providing a tubehaving a longitudinal slot in its top side, which slot terminates at its ends at pointsspaced from the'ends of the tube, inserting the open bottom end'of the siphonbody in said slot and then welding said bodyand tube together, the ends ofsaid tube beyond the slot forming an inlet and a secondary outletfor the finished siphon.

3. The method of making thermic siphons which consists in providing a fiat hollow siphon body open at its top and bottom and end of the siphon body in said slot, forming the rear end of said tube out of its. normal plane so that it may be fixed in its associated sheet in the firebox and then welding said body to the tube, the ends of said tube beyond the closed ends of the body forming the inlet and a secondary outlet for the finished siphon.

4. The method of making a thermic siphon which consists in forming a sheet to the desired pattern and then folding it transversel into flat tubular form to provide a fiat hollow tubular body open at its top and bottom and closed at one end, welding the other end of said body to there provide a second closed end, providing a tube having a flangeless slot formed in the top side thereof short of the ends thereof and adapted to receive the open bottom end of said body and then welding said end of the body in said slot.

5. A siphon of the kind described embodying therein a flat tubular body open at both the top and bottom and closed at both ends and a tube having a slot in the top thereof in which the bottom end of the body is welded, the tube having end portions one of which is formed to extend substantially parallel with one end of said body, the other end of said tube forming substantially an extension of the mid portion of the tube and providing the inlet neck for the finished siphon.

In testimony whereof, I have hereunto set my hand, this 10th day of December, 1929.

GUST J. CHRISTENSON. 

